In this study the effects of rehabilitation teaching plus exercise testing on perceived self-efficacy for and performance of daily activities were compared with and without exercise training. Subjects were patients who had had myocardial infarction or cardiac surgery (mean age 57.7 +/- 11.3 years) and who had already received inpatient rehabilitation services. Subjects were randomly assigned to one of three groups. Treatment group 1 (n = 11) received teaching, treadmill exercise testing, and exercise training (three times weekly for 5 weeks). Treatment group 2 (n = 15) received only teaching and exercise testing. The control group (n = 14) received only routine care without supervised exercise or teaching. Measurements of self-efficacy and activity performance were made at hospital discharge and at 4 and 9 weeks after the cardiac event. Repeated-measures analysis of variance showed an increase in self-efficacy scores (p less than 0.001) and performance of physical activity (p less than 0.001) for all groups. Both treatment groups, especially the training group, obtained the highest scores, but differences between groups were nonsignificant (p greater than 0.05). These results indicate that in a sample of uncomplicated, motivated patients who had participated in a phase 1 inpatient rehabilitation program, substantial improvements in self-efficacy and performance of daily activities were made early in recovery, before the onset of phase 2, formalized outpatient therapy.